1509 results about "Multiple quantum" patented technology

Tailored doping of barrier layers enables balancing of the radiative recombination among the multiple-quantum-wells in III-Nitride light-emitting diodes. This tailored doping enables more symmetric carrier transport and uniform carrier distribution which help to reduce electron leakage and thus reduce the efficiency droop in high-power III-Nitride LEDs. Mitigation of the efficiency droop in III-Nitride LEDs may enable the pervasive market penetration of solid-state-lighting technologies in high-power lighting and illumination.

The invention relates to the technical field of semiconductors, and particularly discloses a multiband LED chip and a preparation method thereof, and a white light LED light source, the LED chip comprises a light-emitting layer, and the light-emitting layer comprises a first cyan light multi-quantum well layer, a second long-wave blue light multi-quantum well layer, a third short-wave blue light multi-quantum well layer and a fourth purple light multi-quantum well layer which are sequentially stacked in the epitaxial direction; the first cyan light multi-quantum well layer, the second long-wave blue light multi-quantum well layer, the third short-wave blue light multi-quantum well layer and the fourth purple light multi-quantum well layer are each of a periodic structure formed by alternately stacking well layers and barrier layers, and the light-emitting wavelengths of the first cyan light multi-quantum well layer, the second long-wave blue light multi-quantum well layer, the third short-wave blue light multi-quantum well layer and the fourth purple light multi-quantum well layer are sequentially decreased. And the forbidden band widths of the barrier layers are sequentially decreased. According to the LED chip, the overall excitation efficiency can be effectively improved, and the output full-spectrum white light LED light source is higher in color rendering index, better in stability, less in damage to human eyes and high in light emitting efficiency.

The invention discloses a light-emitting diode epitaxial wafer, a preparation method thereof and a light-emitting diode, and relates to the technical field of semiconductors. The light-emitting diode epitaxial wafer comprises a substrate, a buffer layer, an N-type semiconductor layer, a low-temperature stress release layer, a multi-quantum well light-emitting layer, an electron blocking layer and a P-type semiconductor layer. The multi-quantum well light-emitting layer comprises a first sub-layer, a second sub-layer, a third sub-layer and a fourth sub-layer which are stacked in sequence, and each of the first sub-layer, the second sub-layer, the third sub-layer and the fourth sub-layer comprises an InGaN quantum well layer and a GaN quantum barrier layer which are periodically and alternately stacked; an electron injection layer is inserted into at least one of the GaN quantum barrier layer of the first sub-layer, the GaN quantum barrier layer of the second sub-layer and the GaN quantum barrier layer of the third sub-layer; and a hole injection layer is inserted into the GaN quantum barrier layer of the fourth sub-layer. By implementing the invention, the electron hole matching degree of the multi-quantum well light-emitting layer can be improved, so that the luminous efficiency of the light-emitting diode is improved.

The invention discloses a Micro-LED epitaxial structure suitable for low working current density and a preparation method thereof, and relates to the technical field of semiconductor devices. The Micro-LED epitaxial structure comprises a substrate, a buffer layer, an N-type semiconductor layer, a low-temperature stress release layer, a multi-quantum well light-emitting layer and a P-type semiconductor layer. The multi-quantum well light-emitting layer comprises a first short-wave multi-quantum well layer, a second long-wave multi-quantum well layer and a third short-wave multi-quantum well layer which are sequentially arranged from bottom to top; the In component in the first short-wave multi-quantum well layer and the In component in the third short-wave multi-quantum well layer are both smaller than the In component in the second long-wave multi-quantum well layer. According to the Micro-LED epitaxial structure, the quality of a multi-quantum well light-emitting layer can be remarkably improved, the matching degree of electron hole concentration in a light-emitting quantum well area is improved, the radiation recombination efficiency of the light-emitting quantum well area is improved, and therefore the lighting effect of a Micro-LED chip under the low working current density is improved, and the service life of the Micro-LED chip is prolonged. The problem that an epitaxial structure of a traditional visible light LED is low in luminous efficiency under the low working current density is solved.

Quantum computing systems require methods to control energies of qubits and couplers for quantum operations. Flux biasing of qubits and quantum couplers is provided for a superconducting quantum computer using single-flux-quantum (SFQ) technology. This method is applicable to a wide range of superconducting qubit structures and couplers, including transmons, fluxoniums, flux qubits, phase qubits and other superconducting qubits. This method enables arbitrary-amplitude time-varying flux biasing of qubits and couplers, due to a sequence of high-speed SFQ pulses. Several preferred embodiments are disclosed which provide high-fidelity control of fast single-qubit and multi-qubit operations.

The invention relates to the technical field of semiconductor devices, in particular to a multi-wavelength light emitting diode and a light emitting module. According to the multi-wavelength light-emitting diode, a multi-quantum well layer comprises n groups of quantum well light-emitting units with different forbidden bandwidths; the n group of quantum well light-emitting units and the (n-1) group of quantum well light-emitting units meet at least one of the following characteristics: (a) the concentration of In in at least one well layer of the n group of quantum well light-emitting units is greater than the concentration of In in at least one well layer of the (n-1) group of quantum well light-emitting units; and (b) the thickness of at least one well layer of the n group of quantum well light-emitting units is greater than that of at least one well layer of the (n-1) group of quantum well light-emitting units. Through the arrangement of the multiple groups of quantum well light-emitting units, under the condition that multiple wavelengths can be generated, stress is fully released, and the photoelectric conversion efficiency is improved.

The invention discloses a light-emitting diode epitaxial wafer and a preparation method thereof, and relates to the field of semiconductor photoelectric devices. The light-emitting diode epitaxial wafer sequentially comprises a substrate, a buffer layer, an N-type GaN layer, a multi-quantum well layer, an electron blocking layer and a P-type GaN layer. The buffer layer sequentially comprises a first AlN layer, a second AlN layer, a third AlN layer, a first superlattice layer, a first AlGaN layer, a second superlattice layer and a first GaN layer; the first superlattice layer comprises a fourth AlN layer and a second AlGaN layer which are alternately stacked, and the second superlattice layer comprises a third AlGaN layer and a second GaN layer which are alternately stacked; a first V-shaped pit extending to the second superlattice layer is formed in the third AlN layer, a second V-shaped pit is formed in the first superlattice layer, and the second V-shaped pit is filled and leveled up by the first AlGaN layer; the second superlattice layer forms a third V-shaped pit, and the first V-shaped pit and the third V-shaped pit are filled and leveled up by the first GaN layer. By implementing the invention, the luminous efficiency can be improved.

The invention discloses an image classification method based on a multi-quantum filtering convolutional neural network, and the method comprises the steps: compressing a pixel value of an obtained image, and coding the compressed pixel value into a corresponding quantum state through a quantum revolving door; and inputting the quantum state into a quantum convolutional neural network to obtain an image label predicted value, training the quantum convolutional neural network by using the predicted value and a loss function to obtain a trained quantum convolutional neural network, the quantum convolutional neural network including a quantum convolutional layer, a quantum measurement attention layer, a pooling layer and a full connection layer, the quantum convolution layer comprises G quantum filters; and inputting an image needing to be detected into the trained quantum convolutional neural network to complete image classification. According to the method, the multi-topology quantum convolutional neural network is combined with a quantum bit measurement attention mechanism, so that the problem of great loss of entanglement information in a measurement stage is effectively solved, the method can better adapt to a quantum calculation environment, and the advantages of quantum calculation are exerted.

A GaN-based blue-green LED epitaxial structure, relating to the field of semiconductor photoelectric devices. The GaN-based blue-green LED epitaxial structure comprises a substrate, and a buffer layer, a dislocation regulation layer, a U-GaN layer, an N-GaN layer, a multi-quantum-well layer, an electron blocking layer and a P-GaN layer which are sequentially stacked on the substrate, wherein the dislocation regulation layer is of a periodic structure with the number of periods ranging from 2 to 10, and each period comprises a GaN layer and an Si-doped GaN layer that are sequentially stacked. The crystal quality of the epitaxial structure can be improved, thereby improving the light-emitting efficiency and the antistatic performance of the blue-green LED based on the epitaxial structure.

A quantum computing service provides a quantum algorithm development kit that enables a customer to define a quantum task, a quantum algorithm, or a quantum circuit using an intermediate representation. The quantum computing service is then configured to automatically translate the quantum task, quantum algorithm, or quantum circuit into a specific representation specific to a particular quantum computing technology selected by the customer to be used to execute the customer's quantum task, quantum algorithm, or quantum circuit.

The invention belongs to the technical field of network communication, and particularly relates to an SPA single packet authentication method based on quantum cryptography, which comprises the following steps: a client and a server establish a shared quantum key pool, and the quantum key pool comprises a plurality of quantum key segments with different life cycles; the client selects one key segment in the quantum key pool, and generates a dynamic key according to the session ID and the random number seed; acquiring a data abstract according to the single packet data; generating an authentication label containing a quantum watermark according to the data abstract and the quantum random number; the client sends a data packet containing the single packet data, the authentication tag and the key fragment index to the server; the server obtains a local key fragment from a local quantum key pool according to the key fragment index, generates a local dynamic key in combination with the same session ID and the random number seed, and performs hash operation on single packet data to obtain a local authentication tag; and the server carries out authentication comparison on the local authentication tag and the received authentication tag.

The invention relates to the technical field of photoelectricity, and discloses a Micro LED epitaxial wafer, a preparation method thereof and a Micro LED chip, the Micro LED epitaxial wafer comprises a substrate, and the substrate is sequentially provided with a buffer layer, an N-type GaN layer, a multi-quantum well layer and a P-type GaN layer; the first multi-quantum well layer comprises at least one group of a first InGaN quantum well layer, a first AlGaN / GaN superlattice layer and a first GaN quantum barrier layer which are stacked in sequence, and the second multi-quantum well layer comprises at least one group of a second InGaN quantum well layer, a second AlGaN / GaN superlattice layer and a second GaN quantum barrier layer which are stacked in sequence. And the third multi-quantum well layer comprises at least one group of third InGaN quantum well layer, hole injection layer and third GaN quantum barrier layer which are stacked in sequence. According to the Micro LED epitaxial wafer provided by the invention, the lighting effect of a Micro LED chip under low working current density can be improved.

The invention relates to the technical field of semiconductor devices, in particular to a low-working-current-density green light Micro-LED epitaxial structure and a preparation method thereof. The epitaxial structure comprises a substrate, a buffer layer, an N-type semiconductor layer, a low-temperature stress release layer, a multi-quantum well light-emitting layer and a P-type semiconductor layer. The electron blocking layer is not arranged on the multi-quantum-well light-emitting layer, the multi-quantum-well light-emitting layer comprises four sub-layers including a first light blue light multi-quantum-well layer, a second blue light multi-quantum-well layer, a third green light multi-quantum-well layer and a fourth light blue light multi-quantum-well layer, and the In component content in the third green light multi-quantum-well layer is larger than that in other layers. The third cyan light multi-quantum well layer is a main light-emitting unit and is not provided with an electron blocking layer, so that the blocking effect on hole injection can be eliminated, the hole injection efficiency of the P-type semiconductor layer is remarkably improved, and the matching degree of electron hole concentration in a multi-quantum well light-emitting layer region is improved.

The invention relates to the technical field of photoelectricity, and discloses a light-emitting diode epitaxial wafer and a preparation method thereof, and an LED, the light-emitting diode epitaxial wafer comprises a substrate, and the substrate is sequentially provided with a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer; the multi-quantum well layer comprises a high-barrier multi-quantum well layer, a middle-barrier multi-quantum well layer, a low-barrier multi-quantum well layer and a low-barrier end multi-quantum well layer which are stacked in sequence. According to the light-emitting diode epitaxial wafer provided by the invention, the hole injection efficiency of the P-type semiconductor material can be improved, the phenomenon of insufficient hole concentration in the multi-quantum well layer is improved, and the matching degree of electron hole concentration in the multi-quantum well layer is improved, so that the radiation recombination efficiency in the multi-quantum well layer is improved, and the brightness and the lighting effect of an LED device are finally improved.

The invention relates to the technical field of semiconductor devices, in particular to a multi-wavelength light emitting diode and a light emitting module. The multi-wavelength light-emitting diode comprises a multi-quantum well layer, wherein the multi-quantum well layer comprises at least m groups of light-emitting regions for generating light with different wavelengths along a first direction; a first well layer, closest to a first light-emitting region of the N-type semiconductor layer, in the multi-quantum well layer has the highest In concentration or the minimum forbidden bandwidth; the second light-emitting region is arranged on the first light-emitting region, and the forbidden bandwidth of the second well layer is greater than or equal to that of the first well layer; the third light-emitting region is arranged on the second light-emitting region, and the forbidden bandwidth of the third well layer is larger than that of the second well layer; a buffer region is arranged in the multi-quantum well layer and is arranged between the first light-emitting region and the second light-emitting region or in the second light-emitting region; the forbidden bandwidth of the buffer region is greater than that of the second well layer. According to the light-emitting diode, by arranging the buffer area and matching with parameter setting of other light-emitting areas, lattice mismatch can be relieved, the crystal quality of the light-emitting areas can be improved, and the light-emitting efficiency can be improved.

The invention relates to a deep ultraviolet light-emitting diode with a light scattering structure and a preparation method of the deep ultraviolet light-emitting diode. The light-emitting diode comprises a substrate layer, a buffer layer and an N-type semiconductor transmission layer which are sequentially arranged along the epitaxial growth direction of a chip, wherein the shape of the N-type semiconductor transmission layer is divided into an upper part and a lower part, and the multi-quantum well active layer, the P-type semiconductor transmission layer and the P-GaN contact layer sequentially cover the surface of the upper part of the N-type semiconductor transmission layer; a horizontal light scattering structure layer and a vertical light scattering structure are respectively distributed in the upper part and the lower part of the N-type semiconductor transmission layer. According to the invention, the scattering effect of light in the N-type semiconductor transmission layer is improved, the optical waveguide effect of the N-type semiconductor transmission layer is broken, the light is effectively prevented from spreading to the metal n electrode, meanwhile, the light can be scattered, the bottom light emitting efficiency of the deep ultraviolet LED is improved, and the light extraction efficiency is improved.

According to the program behavior intervention method based on the quantum state, the target program state is quantized, the quantum state is generated, synchronous monitoring of multiple program behaviors is achieved through the quantum entanglement effect, and the malicious behavior tendency of the program is detected by defining the quantum threshold function; the program quantum state is intervened by using a quantum control operator, so that the program state is adjusted and malicious behaviors are prevented; in addition, a random disturbance term is introduced to increase system complexity, and an intervention strategy is dynamically adjusted through multiple quantum state measurement and feedback, so that control parameters are optimized. According to the method, the problems of insufficient detection precision and weak defense capability when a traditional program behavior detection technology is used for processing complex program behaviors are effectively solved, the safety and the stability of the system are remarkably improved, and the detection and defense capability on complex malicious behaviors is enhanced.

The invention discloses a light-emitting diode epitaxial wafer, a preparation method thereof and a light-emitting diode, and relates to the field of semiconductor photoelectric devices. The light-emitting diode epitaxial wafer sequentially comprises a substrate, a buffer layer, an intrinsic semiconductor layer, an N-type semiconductor layer, a multi-quantum well layer, an electron blocking layer and a P-type semiconductor layer. The P-type semiconductor layer comprises a Si3N4 layer, a first superlattice layer and a second superlattice layer which are sequentially stacked on the electron blocking layer, the first superlattice layer comprises a Mg-doped Al < x > Ga < 1-x > N layer and a Mg-doped GaN layer which are alternately stacked, and the second superlattice layer comprises a non-doped GaN layer and a Mg-doped In < y > Ga < 1-y > N layer which are alternately stacked. By implementing the invention, the luminous efficiency of the light-emitting diode can be improved.

The invention relates to the technical field of semiconductor devices, in particular to a multiband light-emitting diode epitaxial structure and a preparation method thereof. The multiband light-emitting diode epitaxial structure sequentially comprises a substrate, a buffer layer, an N-type semiconductor layer, a low-temperature stress release layer, a multi-quantum well light-emitting layer, an electron blocking layer and a P-type semiconductor layer from bottom to top, the multi-quantum well light-emitting layer comprises four sub-layers, namely a first long-wave cyan light multi-quantum well layer, a second short-wave cyan light multi-quantum well layer, a third long-wave blue light multi-quantum well layer and a fourth short-wave blue light multi-quantum well layer which are sequentially stacked and grown from bottom to top, and the light-emitting wavelengths are sequentially decreased. Meanwhile, by combining the design of the sub-layers of the multiple quantum well light-emitting layers and through the synergistic effect of exciting light of all wave bands, the overall excitation efficiency can be improved, full-spectrum white light is output, the full-spectrum white light is closer to sunlight, the light-emitting efficiency is high, the color rendering property is good, the stability is better, and harm to human eyes is small.

The invention provides a quantum well, a multi-quantum well epitaxial structure and a preparation method thereof, and belongs to the field of semiconductor lasers. The invention provides a quantum well which is of a multi-layer structure and comprises alternate quantum barrier layers and quantum well layers. The array substrate further comprises a gradient buffer layer. The adjacent quantum barrier layer and quantum well layer are combined through a gradient buffer layer; the bottom layer and the top layer in the multi-layer structure are quantum barrier layers; in a unit formed by the connected quantum barrier layer, gradual change buffer layer and quantum well layer, with the quantum barrier layer as the beginning and the adjacent quantum well layer as the end, the size of the gradual change buffer layer in the horizontal direction is gradually reduced, the emission wavelength of the gradual change buffer layer is gradually increased in the direction from beginning to end, and the emission wavelength of the gradual change buffer layer is gradually increased. The initial emission wavelength of the gradient buffer layer is consistent with the emission wavelength of the quantum barrier, and the final emission wavelength of the gradient buffer layer is smaller than the emission wavelength of the quantum well. The quantum well has a high carrier migration rate, a high refractive index and a high optical confinement factor.

The invention provides a patterned photonic crystal laser and a preparation method thereof, the laser comprises a substrate, and a first mask layer, a photonic crystal layer and a second mask layer which are sequentially deposited on the substrate, a light emitting area is etched in the central area of the second mask layer, and transparent conductive layers are deposited on the surface of the second mask layer and the light emitting area; a p-annular electrode is arranged on the surface of the transparent conductive layer on the second mask layer, and an n-annular electrode is arranged below the substrate; the photonic crystal layer is composed of a nanorod array and a polymer filled in gaps of nanorods; holes distributed in a patterned array are etched in the surface of the first mask layer, and nanorods are epitaxially grown in hole areas; the nanorod is formed by sequentially depositing a substrate contact layer, a first waveguide layer, a multi-quantum well layer, a second waveguide layer, a coating layer and a component gradient layer. According to the invention, through collaborative design optimization of all the layers, emission of laser with specific wavelength and preparation of a laser emitting laser with single longitudinal mode, narrow linewidth and stable wavelength are realized.

The invention discloses a GaN-based blue-green light LED epitaxial structure and a preparation method thereof. The GaN-based blue-green light LED epitaxial structure comprises a substrate, and a buffer layer, a 3D layer, a U-GaN layer, an N-GaN layer, a multi-quantum well layer, an electron blocking layer and a P-GaN layer which are stacked on the substrate in sequence, the multi-quantum well layer comprises a shallow well transition layer, a high-temperature quantum well layer, a stress release layer and a low-temperature quantum well layer which are sequentially stacked, and the stress release layer comprises AlN layers and GaN layers which are periodically and alternately stacked. By implementing the invention, the luminous efficiency of the light-emitting diode under high current density can be effectively improved.

The invention relates to the technical field of semiconductor materials, and discloses an LED epitaxial structure with high luminous efficiency and a preparation method of the LED epitaxial structure with high luminous efficiency. Comprising a substrate, and a buffer layer, an undoped GaN layer, an n-type doped GaN layer, a multi-quantum well layer, an electron barrier layer, a p-type doped GaN layer and a hole tunneling layer which are sequentially stacked on the substrate. By implementing the invention, a PN junction is formed in the hole tunneling layer, so that a built-in cell can be formed, the current expansion effect is effectively improved, the tunneling probability of holes can be obviously improved, the luminous efficiency of an LED is improved, and meanwhile, the working voltage can be reduced.

The invention discloses a Micro-LED epitaxial wafer and a preparation method thereof, a multi-quantum well light-emitting layer of the Micro-LED epitaxial wafer comprises a first sub-layer, a second sub-layer and a third sub-layer which are stacked in sequence, and each of the first sub-layer, the second sub-layer and the third sub-layer comprises a pre-well protection layer, an InGaN quantum well layer, a post-well protection layer and a quantum barrier layer which are periodically and alternately stacked; the In component proportion of the InGaN quantum well layer in the first sub-layer and the third sub-layer is smaller than the In component proportion of the InGaN quantum well layer in the second sub-layer; the well front protection layer comprises a first InGaN well front protection layer, an AlGaN well front protection layer and a second InGaN well front protection layer which are stacked in sequence, and the well rear protection layer comprises an InGaN well rear protection layer, an AlGaN well rear protection layer and a GaN well rear protection layer which are stacked in sequence. According to the invention, the light-emitting brightness of the Micro-LED can be improved.

The invention discloses a red light Micro light emitting diode epitaxial wafer and a preparation method thereof. The epitaxial wafer comprises a GaAs substrate, an N-type layer, a multi-quantum well active layer and a P-type layer which are sequentially arranged from bottom to top, the multi-quantum well active layer comprises a plurality of AlGaInP quantum well layers and quantum barrier layers which are alternately arranged, a hole injection layer is inserted between at least part of quantum well structures, and the hole injection layer is composed of a first N-type doped sub-layer, a P-type doped sub-layer and a second N-type doped sub-layer which are connected in sequence; the materials of the three sub-layers are (Al < x > Ga < 1-x >) < 0.5 > In < 0.5 > P (x is greater than or equal to 0.5 and less than or equal to 0.9), and the doping concentration is in gradient distribution along the thickness direction. By introducing the N-P-N structure hole injection layer, the hole injection efficiency is improved, electron leakage and Mg diffusion are inhibited, and the luminous efficiency of the red light Micro LED is remarkably improved.

The invention provides a GaN-based alpha particle detector and a preparation method thereof, the GaN-based alpha particle detector comprises a substrate and an epitaxial structure epitaxially formed on the substrate, and the epitaxial structure comprises a multi-quantum well layer. A multi-quantum well layer is introduced, the multi-quantum well layer absorbs incident energy of alpha particles and correspondingly excites a large number of electron-hole pairs, and the electron-hole pairs are limited in quantum wells by the quantum confinement effect of the multi-quantum well layer, so that not only is the loss of electron-hole pair diffusion and recombination reduced, but also the service life of current carriers is prolonged, and the performance of the device is improved. The carrier collection efficiency of the alpha particle detector is greatly improved, and more electron-hole pairs can be collected and converted into electric signals to be output, so that the performance of the alpha particle detector is improved.

The invention relates to a quantum network data transmission method and system for multi-quantum-bit communication, and belongs to the technical field of quantum communication and network. According to the method, an E2E entanglement generation mechanism and a specific noise interference mechanism of multi-quit communication in the quantum network are established, a multi-quit entanglement quality evaluation model, an E2E communication time delay model and a request data transmission model are modeled, and a centralized and distributed collaborative optimization network response model is designed. According to the system, a proposed multi-quit entanglement communication framework is trained and deployed on quantum network models of different scales, the system is used for processing transmission requirements of heterogeneous requests in batches, and stable and efficient data transmission service can be provided for concurrent response of batch requests in a large-scale quantum network. According to the invention, resource configuration and transmission quantification can be carried out on entanglement establishment and entanglement transmission, the response time delay of a large-scale quantum network to a multi-request transmission demand is reduced, and quantum resources are reasonably used.

The invention discloses a light-emitting diode epitaxial wafer and a preparation method thereof, and relates to the technical field of semiconductors. The light-emitting diode epitaxial wafer comprises a substrate, and a buffer layer, a non-doped GaN layer, an N-type GaN layer, an electron dredging layer, a multi-quantum well layer, an electron blocking layer and a P-type GaN layer which are stacked on the substrate in sequence, the electron dredging layer comprises a first sub-layer, a second sub-layer, a third sub-layer and a fourth sub-layer which are sequentially stacked, the first sub-layer is a Si3N4 layer, the second sub-layer comprises an AlGaN layer, a first InGaN layer and a first GaN layer which are periodically and alternately stacked, the third sub-layer comprises a second GaN layer and a second InGaN layer which are periodically and alternately stacked, and the fourth sub-layer is a Si3N4 layer. And the fourth sub-layer comprises an AlInGaN layer, a third InGaN layer and a third GaN layer which are periodically and alternately stacked. According to the invention, while the electronic expansibility is improved, excessive electrons are prevented from entering the multi-quantum well layer to generate electron overflow.

Provided is an optical transmitter having high manufacturing stability and a high reflection suppression effect. In the optical transmitter, a distributed feedback (DFB) laser having an active region formed as a multiple quantum well that generates an optical gain by current injection and a diffraction grating, an electro-absorption (EA) modulator having an absorption region formed as a multiple quantum well having a composition different from a composition of the DFB laser, a semiconductor amplifier (SOA) having an active region having a same composition as the composition of the DFB laser, a bent waveguide that rotates a light propagation direction by an angle θwg, and a passive waveguide connected to the SOA and including a core having a band gap wavelength shorter than an oscillation wavelength of the DFB laser are monolithically integrated on one substrate. The passive waveguide has a tapered region and a narrow waveguide region. The tapered region converts a width W1 of the passive waveguide connected to the SOA into a width W2 of the narrow waveguide region, and the passive waveguide forms the angle θwg with respect to a normal line to an end surface of the substrate and is in contact with the end surface of the substrate.

The invention discloses a chip structure capable of simultaneously improving deep ultraviolet LED crystal quality and injection efficiency and a preparation method. The chip structure comprises a substrate, a buffer layer is arranged on the substrate, a multi-quantum well layer is arranged above the buffer layer, an n-type doping layer is arranged on the side face of the multi-quantum well layer, and an n-type contact electrode is arranged above the n-type doping layer. A plurality of p-type doped layer plugs are inserted in the multi-quantum well layer, a p-type doped layer is arranged above the p-type doped layer plugs and the multi-quantum well layer, and a p-type contact electrode is arranged on the p-type doped layer; a passivation layer is arranged on the upper surface of the whole structure, and the thickened metal electrode penetrates through the passivation layer and is located on the n-type contact electrode and the p-type contact electrode. According to the invention, insufficient hole injection in the multi-quantum well layer and the crystal quality of the multi-quantum well layer can be improved at the same time.